valletta



Feb. 24, 1931.

VARIABLE SPEED GEARING PARTICULARLY FOR MOTOR VEHICLES Filed Nov. 19,1929 Fig.1 2 1c 5 33 39 1:0 a I 491 I l a? V/A 35 k QLQFA as v.VALLETTA, 1,794,264

Patented Feb. 24, 1931 were!) ST- irs PATENT OFFICE v rronro vannnr'ra,or rum, ITALY, Assronon '10 FIAT socrErA momma, or

roam, ITALY .nnsr'nrzo enanmc, PARTICULARLY non moron VEHICLESApplication filed Hovember 19, 1929, Serial No. 408,293, and in ItalyDecember 12, 1828.

This invention relates to avariable speed caring with sets of internallytoothed gears the type described in my co-pending patt application Ser.No. 351,971, filed April 2. v, nd application of "lurpose is to make themechanism cheaper and easier in construction and operation.

An object of my invention is to provide a variable speed gearing inwhich the C-shaped ring is made in two parts fixed together by of screwsor bolts in order to facilitate Another object of my invention is toprogearing in which the L member for the lower speeds is able on thetransmission shaft, inof on the countershaft (as described in previousapplications), and therefore on same shaft as the sliding member for theer speeds. nether object of my invention is to provariabie speedgearing, in which the sport for the C-shaped ring is strengthby avoidingslots therein, the counterbeing driven by a gear cut on the last iinternaliy toothed member, i. e. on the opposite side of this latterwith respect to the i -shaped ring.

The accompanying drawing shows, by way example, an axial longitudinalsection of construction.

gear

arts 1 and 1a and houses the engine and the countershaft 3. The enginecarries the pinion 6 in gear with the ii ernal set of teeth 7 of theC-shaped rin ich is formed in two parts 8a: 8b connects together byscrews 80. While the ring portion 8a carries the said internal set ofteeth so i, the portion 85 carries the external set of teeth 9 in gearwith the internal teeth 10 of the crown 11 having the hub or sleeve 12.The pinions 7 and 9 of the ring 8a-8b being eccentric to the axis of theengine shaft 2, supported by the support 14 eccentrically '2? aredisplaced with respect to said axis and gripped between the two sections1-1a of the gearbox. 1n the support 14 a member 16 having a partco-axial with the shaft 2 car- 5? ries the ball bearing 17 for thislatter. The

even date and its .136, the latter being but slightly displacedrelatively to the pinion 4.- cut on the hub 12 and meshing with thepinion 5 keyed on the countershaft 3.

The engine shaft 2 reaches within the bell 20 of the transmission shaft22 supported by a bearing 26, two ball bearings 23a and 24 for mutuallysupporting the shafts 2 and 22 bein interposed between the shaft 2 andthe befi 20. The ball bearings 23a and 2 1 also absorb the reaction ofthe pinion pairs 27 :28 and 29:30 when one or the other is renderedoperative for the second or first speed.

The sets of teeth 28 :30 form part of a gear member slidable by a fork(not shown) engaging the collar 31, said member being feathered on thebell 20. The co-acting sets of teeth 27:29 form part of a non-slidablegear member keyed on the countershaft 3. The sleeve 19, moved by a fork(not shown) engaging the collar21, slides Within the bell 20 by means ofco-acting The sleeve 18 is fixed to the engine shaft 2 and is providedwith dog teeth 18a meshing with the teeth 19a of the sleeve 19 when thislatter is moved towards the right; in this case the engine shaft isdirectly connected with the transmission shaft 22. The hub 12 of thecrown 11 is provided with dog teeth 12a meshf.

The hub teeth and grooves.

' ing 32 carried by a socket 1c in the gearbox 1 and by a bearing 33carried by the box 1. A

thrust bearing 34 absorbs the front reaction of the transmission. Thebearings fixed to the gearbox 1:1a are protected by covers 35 and 36,the former of which is provided with a small case 35a enclosing the wormwheel 37 and worm 38 driving a speedometer.

On the shaft 22 is keyed the sleeve 39 carrying the wheel 37 with theflange 40 for coupling with the transmission of the vehicle.

The gearbox 1:1a is provided with a top cover and the members foroperating the variable speed gears (levers, rods, forks, etc.) are ofthe usual type.

The working is as follows: With the various gearing members in theposition shown, the first speed is obtained by throwing the toothedwheel 30 into gear with the toothed wheel 29, the second speed bythrowing the toothed wheel 28 into gear with the toothed wheel 27 thethird speed by returning the toothed wheels 28 and 30 into the positionshown and by displacing the movable clutch member 19 to the left sets tothrow the teeth 195 into gear with theteeth 12a and finally the fourthspeed is obtained by displacing the movable clutch member 19 to theright so as to cause the teeth 19a to mesh with the teeth 180.

It is clear that the constructional details may be varied according tothe type of gearing, the number of gear ratios, the engine power etc.without departing from the scope of the invention.

What I claim is:

1. A variable speed gearing comprising a gear-box, an engine shafthaving one end projecting into the box, a pinion on said shaft, atransmission shaft having a bellshaped end in which the projecting endof the engine shaft is coaxially supported, a two-part C- haped ringeccentri'cally d 1sposed with respect to the axis of the engine andtransmission shafts, internal teeth on one part of said ring meshingwith the pinion pinions on the counter shaft, gears carried.

by the bell-shaped end of the transmission my invention,

shaft movable into and out of mesh with the pinions on the countershaft, a double clutch member axially movable within the bell, teeth onthe engine shaft for engagement with the clutch, and teeth on the sleevefor engagement with said clutch.

2. A variable speed gearing comprising a gear-box, an engine shafthaving one end projecting into the box, a pinion on said shaft, atransmission shaft having a bellshaped end, hearings in the lattersupporting the engine shaft, a two-part C-shaped ring eccentricallydisposed with respect to the axis of the engine and transmission shafts,internal teeth on one part of said ring meshin with the inion on theengine shaft, externa teeth on t 6 other part of said ring, a sleeverotatably mounted on the engine shaft having an internally toothed crownmeshing with the external teeth of said ring, an annular support,bearings in the latter supporting said rin in the plane of the teeth,fl'PlIllOIl on said sleeve, a bearing between the latter and the engineshaft in the plane of the pinionon the sleeve, a counter shaft, a pinionon the latter meshing with the inion on the sleeve, gears on thecouriter sha t, gears axially movable on the bellshaped end alternatelymovable into mesh with the gears on the counter shaft, a double clutchmember axially'movable in said bellshaped end, and teeth on the engineshaft and on the sleeve for alternateengagement with the double clutchmember.

In testimony that I claim the foregoing as I have signed m name.V'ITTORIO V LETTA.

.on the engine shaft, external teeth on the

